MMP13
MMP13 (matrix metalloproteinase 13) is an enzyme made by cartilage cells that cuts type II collagen, the main fibre of cartilage. Higher MMP13 is one of the hallmarks of cartilage cells shifting into a breakdown state.
Also called MMP-13, matrix metalloproteinase 13, collagenase-3.
Oxidative stress is one of the signals that raises it. In cells from healthy human cartilage, hydrogen peroxide raised MMP13 and the aggrecan-cutting enzyme ADAMTS5 while lowering SOX9, and an inflammatory signal and calcium crystals did the same (Rong 2019).
Supporting cartilage glutathione has lowered it in animal and cell studies. Oral NAC held back MMP13 in a rat model of osteoarthritis (Kaneko 2019), and dihydrolipoic acid suppressed it in mouse cartilage cells and in the cartilage of mice (Chen 2026).
Sources
- Rong J, Zhu M, Munro J et al. Altered expression of the core circadian clock component PERIOD2 contributes to osteoarthritis-like changes in chondrocyte activity. Chronobiol Int 2019.
- Kaneko Y, Tanigawa N, Sato Y et al. Oral administration of N-acetyl cysteine prevents osteoarthritis development and progression in a rat model. Sci Rep 2019.
- Chen Y, Fang J, Zhou Z et al. Dihydrolipoic acid suppresses ferroptosis in chondrocytes to ameliorate the progression of osteoarthritis by modulating the FOXO1/TXNIP signaling pathway. Free Radic Biol Med 2026.
Related terms
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